YOKOSUKA, Japan -- The search for seven U.S. Navy sailors missing after their destroyer collided with a container ship off Japan was called off Sunday after they were found dead in the ship's flooded compartments, CBS News national security correspondent David Martin reports.

The U.S. Navy released the names of the deceased sailors on Sunday night.

Vice Adm. Joseph Aucoin, the commander of the Navy's 7th Fleet, described the damage and flooding as extensive, including a big puncture under the waterline. The crew had to fight to keep the ship afloat, he said, and the ship's captain is lucky to have survived.

"The damage was significant, this was not a small collision," he said, adding that the crew's response was "swift and effective."

"Heroic efforts prevented the flooding from catastrophically spreading which could have caused the ship to founder or sink. It could have been much worse," he said.

Navy divers found "a number of" bodies in the ship Sunday, a day after it returned to the 7th Fleet's home base in Yokosuka, Japan, with the help of tug boats. Aucoin, speaking at a news conference at the base, wouldn't say how many bodies were recovered, pending notification of next of kin. He said the remains have been transferred to Naval Hospital Yokosuka.

He said much of the crew of about 300 was asleep when the collision happened at 2:20 a.m. Saturday, and that one machinery room and two berthing areas for 116 crew members were severely damaged.

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U.S. Navy ship collides with Japanese vessel; injuries reported

The U.S. Navy destroyer USS Fitzgerald collided with a Japanese merchant ship off the coast of Japan Friday afternoon. The Fitzgerald made a dist...

"You can't see most of the damage, the damage is mostly underneath the waterline, and it's a large gash near the keel of the ship," he said. "So the water flow was tremendous, and so there wasn't a lot of time in those spaces that were open to the sea. And as you can see now the ship is still listing, so they had to fight the ship to keep it above the surface. It was traumatic."

The Fitzgerald's captain, Cmdr. Bryce Benson, was airlifted from the ship's deck after daybreak Saturday to the U.S. Naval Hospital in Yokosuka with a head injury. Two other crew members suffered cuts and bruises and were also flown out by helicopter.

"His cabin was destroyed, he is lucky to be alive," Aucoin said of Benson.

Acting Secretary of the Navy Sean Stackley says the Navy is deeply saddened and promised a full investigation into the collision.

He said in a statement that "we are all deeply saddened by the tragic loss of our fellow shipmates." He also praised their colleagues for saving the ship from further damage and bringing it back to port.

Japanese Prime Minister Shinzo Abe sent a sympathy message to U.S. President Trump over the fatal collision.

"We are struck by deep sorrow," Abe said in his message to Mr. Trump on Sunday, expressing condolences and sympathy "straight from my heart" to the victims and the injured.

"I express my heartfelt solidarity to America at this difficult time," he wrote, praising U.S. servicemen in Japan under the allies' bilateral security pact.

A member of the U.S. Navy Damage Control Training Team is seen near the U.S. national flag on the Arleigh Burke-class guided-missile destroyer USS Fitzgerald, at the U.S. naval base in Yokosuka, south of Tokyo, Japan, on Sun., June 18, 2017.

Reuters

The container ship ACX Crystal weighs 29,060 tons and is 222 meters -- 730 feet -- long, much larger than the 8,315-ton Navy destroyer. The container ship's left bow was dented and scraped, but it did not appear to have sustained any major structural damage.

All of the ACX Crystal's 20-member Filipino crew were safe, said Japanese shipping company Nippon Yusen K.K., which operates the Philippine-flagged ship.

The Japanese coast guard questioned crew members of the ACX Crystal, and is treating the incident as a case of possible professional negligence, said Masayuki Obara, a regional coast guard official.

Conditions were clear at the time of the collision, though the area is particularly busy with sea traffic.

The victims might have been killed by the impact of the crash or drowned in the flooding, said Navy spokesman Lt. Paul Newell, who led news media on a visit to get a first-hand look at the mangled vessel.

Aucoin wouldn't speculate on the cause of the collision. He said he would order a full and thorough investigation.

Damage is seen on the guided missile destroyer USS Fitzgerald off the Shimoda coast, after it collided with a Philippine-flagged container ship, on Sat., June 17, 2017.